Metal-hydroxycarboxylate interactions: syntheses and structures of K2[VO2(C6H6O7)]2·4H2O and (NH4)2[VO2(C6H6O7)]2·2H2O

Potassium and ammonium dimeric (citrato)dioxovanadium(V) hydrate K₂[VO₂(H₂cit)]₂·4H₂O1 and (NH₄)₂[VO₂(H₂cit)]₂·2H₂O2 (H₄cit=citric acid) have been prepared and characterized by X-ray structure analyses. Vanadate1 crystallizes in the monoclinic space groupP2₁/n (No. 14) with unit cell parameters:a=9.304(2),b=11.756(2),c=11.911(2)Å, =111.72(3)°, andD _c=1.911 g/cm³,Z=2; Vanadate2 also crystallizes in the monoclinic space groupP2₁/n with unit cell parameters:a=9.719(2),b=11.111(3),c=11.294(2)Å, =109.03(2)°, andD _c=1.781 g/cm³,Z=2. Each dimer contains a centro-symmetric planar four-member V₂O₂ ring with two exocyclic citrate entities coordinated by the oxygen atoms of the hydroxy-and -carboxylate ligands, while the other two -carboxylate groups remain uncomplexed. Principal dimensions of the V–O bonds are 1.986(4)_av (hydroxy) and 1.980(3)Å(-carboxyl) for vanadate1, 1.988(2)_av (hydroxy) and 1.974(3)Å(-carboxyl) for vanadate2.     

ZnNb2O6粉体的水热合成研究

以Zn(NO3)2溶液和氧化铌凝胶为原料,分别选取HCI、NaOH等为矿化剂调节pH值,采用水热法制备了ZnNb2O6微波介质陶瓷粉体,利用XRD、SEM等方法表征了所得粉体的相组成、颗粒尺寸大小等.实验结果表明:以Zn(NO3)2溶液和Nb2O5·nHt2O为前驱物按照2:1的化学计量比在碱性条件下200℃反应168 h后,可制得平均晶粒尺寸为29.6 nm的ZnNb2O6粉体.将合成的粉体在400℃热处理,制得颗粒尺寸均匀,分散性良好的ZnNb2O6粉体.将水热合成的ZnNb2O6粉体制成陶瓷,其室温介电常数达到27.9.     

Structure of progesterone hydroquinone monohydrate (1∶1∶1), C21H30O2·C6H6O2·H2O

The crystal structure of progesterone hydroquinone monohydrate was determined by means of X-ray diffraction methods:M _r=442.6, orthorhombic,P2₁2₁2₁,a=14.680(2),b=22.725(3),c=7.334(1) Å,V _a=2446.6(6) ų,Z=4,D _x=1.190 M gm^–3, MoK radiation ,(MoK)=0.75 cm^–1,F(000)=948. The structure was solved usingMultan;R=0.059,R _w=0.059 for 2736 reflections. This progesterone molecule has the most flattenedA ring, relative to the rest of the skeleton, of all progesterone molecules studied so far. Steroid, hydroquinone, and water molecules form, by means of hydrogen bonds, two parallel chains connected with each other by hydrogen bonds.The authors thank Dr. A. Szyczewski for supplying crystals. This research was supported by the project RP.II.10 from the Polish Ministry of National Education and by PHS Grant No. DK26546.     

Silicogermanate Ba2K2In2[(Si0.8Ge0.2)6O18] · 2H2O As an Analogue of the Natural Zirconosilicate Kostylevite K4Zr2[Si6O18] · 2H2O

Crystallography Reports - Crystals of new silicogermanate Ba2K2In2[(Si0.8Ge0.2)6O18] · 2H2O were prepared by the hydrothermal synthesis; sp. gr. P21/n, a = 6.5548(6) Å, b = 11.6946(10)...     

Performance investigation of Li2O–Al2O3–4SiO2 based glass–ceramics with B2O3, Na3AlF6 and Na2O fluxes

Influence of single fluxes (10 wt.% B₂O₃), bi-component fluxes (4 wt.% B₂O₃ + 6 wt.% Na₃AlF₆), and complex fluxes (4 wt.% B₂O₃ + 4 wt.% Na₃AlF₆ + 2 wt.% Na₂O) on the thermal kinetic parameters, microstructure, flexural strength and coefficient of thermal expansion (CTE) of Li₂O–Al₂O₃–4SiO₂ (LAS) glass–ceramics was investigated through differential thermal analysis (DTA), X-ray diffraction (XRD), and scanning electron microscope (SEM). The results showed that complex fluxes could efficiently decrease transition temperature (T_g) and crystallization temperature (T_p), and accelerate the formation of needle-like β-spodumene crystals which benefit high flexural strength. The homogeneous LAS glass–ceramic (sample C₃) which has a high strength of 132.4 MPa and low CTE (100–650 °C) of 2.74 × 10^? 6/°C is obtained by doping of the initial LAS glass by complex fluxes of 4 wt.% B₂O₃, 4 wt.% Na₃AlF₆, and 2 wt.% Na₂O, nucleating at 630 °C/120 min and then crystallized at 780 °C/120 min. It is worthy of further investigation as a bonder of diamond composite material due to its outstanding prosperities.     

Synthesis and crystal structure of [Ni(H2O)6](C19H17O9S)2·2H2O

A water soluble flavonoid sulfate, [Ni(H₂O)₆](C₁₉H₁₇O₉S)₂·2H₂O was synthesized and its structure was determined by single-crystal X-ray diffraction analysis. The crystal of it belongs to triclinic crystal system, space group P–1. The results show that the title compound consists of [Ni(H₂O)₆]²⁺, C₁₉H₁₇O₆SO₃ ⁻ and H₂O. Ni(II) is located on the symmetry center and octahedrally coordinated by six water molecules. A variety of hydrogen bonds among [Ni(H₂O)₆]²⁺, C₁₉H₁₇O₆SO₃ ⁻ and the lattice water molecules build a hydrophilic region. Aromatic π–π stacking interactions assemble isoflavone skeletons into a column and the columns form a hydrophobic region of the title compound. The sulfo-groups bridge the hydrophilic regions and the hydrophobic regions as well as the inorganic components and organic components. Hydrogen bonds, stacking interactions and the electrostatic interactions between cation [Ni(H₂O)₆]²⁺ and anion sulfonate C₁₉H₁₇O₆SO₃ ⁻ lead the moieties to a three-dimensional structure.     

配合物[Cu2(C6H2Cl2OC=N-C3H6COO)2(H2O)2]·3H2O合成与晶体结构

本文以苏氨酸,3,5-二溴水杨醛以及醋酸铜为原料合成了新型配合物[Cu2(C6H2Cl2OC=N-C3H6COO)2(H2O)2]·3H2O,并对其晶体结构经元素分析,红外光谱及X射线单晶衍射表征.结果表明:该晶体属单斜晶体结构,晶胞参数分别为:a=0.6985(2) nm, b=1.0789(2) nm, c=1.9639(3) nm, β=92.182(3) °, Mr=797.34, V=1.4789(6) nm3 , Z=2, Dc=1.790 g/cm3, μ(MoKa) =1.867 mm-1, F(000)=808, R=0.0321, wR= 0.0566.Cu(II)与一个N原子,两个O原子以及一个水分子构成三齿链状席夫碱.不对称单元结构包含两个配合物分子及三个由氢键链接的水分子.     

Interferometric study of the growth kinetics of K2Co(SO4)2 · 6H2O and K2Ni(SO4)2 · 6H2O crystals

Crystallography Reports - The growth kinetics of the (001) and (110) faces of K2Co(SO4)2 · 6H2O and K2Ni(SO4)2 · 6H2O crystals in the kinetic mode has been in situ investigated for the...     

[Co(H2O)6](C18H15O4SO3)2·4H2O的合成和晶体结构

以芒柄花素为先导化合物,合成了水溶性的[Co(H2O)6](C18H15O4SO3)2·4H2O,并采用IR, 1H NMR, TG-DTA, XRD和单晶X射线衍射法对其结构进行了表征.单晶X射线衍射结果表明:[Co(H2O)6]2+、C18H15O4SO 3和H2O之间存在多种氢键,形成晶体结构中的亲水区.异黄酮骨架间反平行排列,面对面和边对面芳香堆积作用同时存在于其中,构成晶体结构中的疏水区.磺酸根是连接亲水区和疏水区的桥梁.氢键、芳香堆积作用以及阴阳离子之间的静电引力共同将标题化合物组装成具有三维网络结构的超分子.     

Synthesis and crystal structure of a new lithium cyclohexaphosphate hydrate: Li6P6O18·10H2O

The synthesis and crystal structure of a novel hydrate of lithium cyclohexaphosphate are reported. Li₆P₆O₁₈·10H₂O crystallizes in the space group C2/c with a = 15.113(5), b = 12.006(2), c = 15.892(2) Å, = 122.85(2)°, and Z = 4. The structure consists of P₆O₁₈ ring layers stacked along the c direction in between which are located the lithiumions and water molecules. Two LiO₄ tetrahedra share common edges with LiO₅ pseudosquare pyramids to form two independant Li₃O₉ units. About 50% of the water molecules have fractional occupancy rates and form fragments of molecules. A linear relationship is established between the relative cell volume V/Z and the hydration degree, n, for all the known hydrates: Li₆P₆O₁₈·nH₂O.     

6.0GPa下NaAlSi2O6翡翠的合成与表征

通过模拟天然翡翠的形成机理,对高温高压技术和玻璃料制取工艺的优化,以Na2SiO3·9H2O和Al2(SiO3)3为原料并添加少量致色剂CrO3,在超高压6.0 GPa下实现玻璃料由非晶态向晶态转化.通过XRD、FTIR和SEM等方法对样品进行表征,实验结果表明:6.0 GPa、1530℃条件下合成样品呈现翠绿色,质地温润,具有较高的润度和透明度;样品主要成分为NaAlSi2 O6,结晶度较高,分子结构为硅氧四面体结构,晶粒细密,致密有序;合成翡翠的硬度和密度等常规宝玉石参数也与天然翡翠接近,我们的研究对于探究翡翠在超高压下形成提供了数据参考.     

α-NiSO4·6H2O晶体生长与光学性质

用水溶液降温法生长出光学品级的α-NiSO4·6H2O大单晶,对晶体的透过光谱和(001)晶面的X射线衍射性能进行了测试和表征.     

[Mn(H2O)6][Bi(edta)2.2H2O的合成与晶体结构

以MnCO3与多胺羧酸铋反应,合成了含铋多金属配合物[Mn(H2O)6][Bi(edta)]2.2H2O,通过元素分析和红外光谱对配合物的组成和结构进行了表征.用热重-差热手段研究了配合物的热分解过程,用x射线单晶衍射法测定了其晶体结构.[Mn(H2O)6][Bi(edta)]2·2H2O属单斜晶系,C2/c空间群,晶胞参数:a=2.37013(4)nm,b=0.87111(2)nm,c=1.61082(3)nm,β=97.273(1).,Z=4,Mr=1193.46,V=3.299.01(11)nm3,Dc=2.403g.cm-3,μ=11.123mm-1,F(000)=2284,R1=:0.0210,wR2=0.0567.大量分子间氢键将整个连接起来形成无限3-D结构.     

Crystal structure of aminoguanidinium hexahydro-closo-hexaborate dihydrate, (CN4H7)2B6H6 · 2H2O

The (HAgu)₂B₆H₆ · 2H₂O compound was synthesized and its crystal structure was determined [R = 0.0385 for 2018 reflections with I > 2σ(I)]. The structure consists of HAgu ⁺ cations, centrosymmetric B₆H ₆ ^2? anions, and water molecules. The anions have an almost regular octahedral structure. The bond lengths and angles lie within the following narrow ranges: B-B, 1.715–1.726(2) Å; B-H, 1.08–1.14(2) Å; B-B-B, 59.72°–60.29(9)° and 89.63°–90.20(11)°; and B-B-H, 133.2°–137.0(9)°. The HAgu ⁺ cations and water molecules are involved in the O-H?O, N-H?O, and N-N?N hydrogen bonds and participate in numerous (N, O)-H?H-B specific interactions with the B₆H ₆ ^2? anions, which results in splitting and high-frequency shift of the band of B-H stretching vibrations in the IR spectrum.     

CaO-MgO-Al2O3-Fe2O3-B2O3-SiO2系微晶釉的制备

通过引入B2O3以降低烧成温度,利用赤泥中的Fe2O3为着色剂,在1150℃左右低温烧成制备了CaO-MgO-Al2O3-Fe2O3-B2O3-SiO2系微晶釉.赤泥的加入量为20;左右时,釉面具有良好的装饰效果和显微硬度.利用XRD、SEM研究了釉的物相及显微组织.结果表明,釉中析出的微晶是普通辉石,微晶的含量随MgO及CaO的含量增加而增加,而提高Al2O3含量则抑制微晶的析出.     

R2O-RO-SiO2-Al2O3-Fe2O3-P2O5系分相釉的研究

针对铁红分相釉的配方特点,采用L8(4 ×24)正交实验研究了钠长石、牛骨灰、滑石、方解石、石英加入量对R2O-RO-SiO2-Al2O3-Fe2O3-P2O5系统分相釉釉面效果的影响,采用扫描电子显微镜(SEM)和能谱分析(EDS)对釉层的微观结构进行了表征.研究发现:牛骨灰对釉面是否出现“柿红”效果影响最显著,而方解石影响最不明显.Si/P摩尔比对铁红色釉面的产生起关键作用,当Si/P摩尔比小于2O,出现铁红釉面效果的概率极高.随着滑石加入量从9份变化到18份,出现铁红色釉面的趋势反而降低.经SEM和EDS分析发现,“柿红色”、“酒红色”釉面效果的产生很大程度上是由于釉层液液分相促进Fe2O3富集或偏析造成,且特别容易在高钠、低镁、低铝处聚集,最终连成雪花状结晶.     

Hydrothermal Synthesis and Characterization of a New Strandberg-type Diphosphopentamolybdate (C6N3H18)2[P2Mo5O23] · 6H2O

Crystallography Reports - An inorganic-organic hybrid material formulated as (C6N3H18)2[P2Mo5O23] · 6H2O, has been hydrothermally synthesized and characterized by single crystal X-ray...     

混合阴离子磷酸盐RbCd6(P2O7)2P3O10的热学与光学特性研究

利用高温固态反应技术合成了一种新型磷酸盐RbCd6(P2 O7)2 P3O10,并用高温熔盐法自发结晶获得了其单晶.X射线单晶衍射分析表明,该物质结构中含有两种孤立的聚阴离子:P2O7二聚体与P3O10三聚体.两种不同的聚阴离子基元共存于一种结构中,在磷酸盐体系中很少见.这一发现不仅丰富了磷酸盐的结构化学,而且为混合阴离子材料的设计提供了新视角.此外,对该物质的热稳定性及光学性能进行了表征.